The invention relates to a method for introducing substantially rectangular pieces of laundry into a laundry treatment apparatus, such as a rotary ironed, and an apparatus for exercising the method.
Apparatuses of this kind are used primarily in large-scale laundries where they are used to smoothed and unfold large pieces of laundry, such as sheets, tablecloths, eider down cases and the like, for subsequent introduction of that piece of laundry into for instance a rotary ironed, where it is important that such feeders efficiently unfold and smoothed the pieces of laundry in order to avoid that unintended press folds occur following the rotary ironed. Most frequently the pieces of laundry are introduced into the apparatus in that a piece of laundry is fetched from a pile of laundry in its wrinkled state and optionally wet or moist, following which the piece of laundry is introduced into the feeder that subsequently treats the piece of laundry such that it can be transferred to for instance a rotary ironed in unfolded and smoothed state.
Today numerous suggested configurations of apparatus that are able to carry out said processes are known. Thus for instance U.S. Pat. No. 2,635,370 teaches an apparatus for smoothing and unfolding large pieces of laundry wherein two narrow conveyor belts are configured in abutment on each other between which the piece of laundry can be introduced and suspended to each side of the lowermost conveyor belt and following which leg air jets can be applied onto the surfaces of the cloth thereby causing the cloth to flutter and be smoothed while suspended in the apparatus. However the apparatus cannot serve as feeder in that the large piece of laundry must subsequently be manually removed from the apparatus and optionally transferred to a rotary ironed. This means that the apparatus cannot in any way whatsoever meet the requirements made to performance efficiency required in today""s industrial laundries.
Published European patent application No. 424,290, on the other hand, teaches an actual feeder that comprises a short and very wide belt conveyor above which the large piece of laundry is pulled into place from its one side in that approximately the middle of an edge of the piece of laundry is inserted into grippers intended therefore that pull the cloth in place across the belt conveyor. This will typically cause the piece of laundry to be located diagonally across the belt conveyor and therefore means are provided for straightening the piece of laundry whereby two opposed edges of the piece of laundry will be caused to be situated perpendicularly to the advancement direction of the belt conveyor. In this situation the piece of laundry is suspended unfolded and smoothed across the belt conveyor and hereby a bar is provided that can transfer the piece of laundry from the belt conveyor to a subsequent cloth treatment apparatus, if any, such as a rotary ironed. However, this presupposes that the piece of laundry is positioned correctly prior to the transfer, which is accomplished by the belt conveyor advancing the piece of laundry a certain distance. Thus all of the above processes are performed while the piece of laundry hangs across the belt conveyor which means that the subsequent transfer of the piece of laundry must be relatively accurate in order to ensure that the piece of laundry is transferred in its unfolded state and with the correct orientation.
EP patent No 666,360 teaches a method and an apparatus whereby the piece of laundry cannot the straightened and unfolded until it has been introduced into the feeder as such. This is performed in that the piece of laundry is suspended across the conveyor with a relatively large side hanging on the one side of the conveyor and a relatively small side on the other side, and wherein the fold with which the piece of laundry lies across the conveyor is lifted by means of a bar that subsequently presses the piece of laundry in between two opposed transport faces that resiliently abut on each other whereby the piece of laundry is transported on the one transport face in the feeder that has means for correctly orienting and unfolding the nieces of laundry. Hereby a relatively high productivity can be obtained for the introduction of pieces of laundry since the initial straightening and unfolding of the pieces of laundry are avoided and can be performed at a later stage in the feeder.
However, it is a problem in this context that, due to the piece of laundry being suspended with its major part on the one side of the conveyor and the entire piece of laundry being lifted upwards for engagement between the two transport faces, a relatively large height of the machinery is required.
Therefore, it is the object of the present invention via to provide a method and an apparatus whereby it is possible to obtain a high degree of efficiency in the introduction process, but whereby the height that is necessary to obtain an effective handling of the pieces of laundry without them touching the support of the apparatus is reduced considerably, ceteris Paribus.
According to the invention this is obtained in that the apparatus comprises means for forming a fold on the substantially freely suspended portions of the piece of laundry and means for introducing the fold thus formed on the piece of laundry (2) between the two opposed transport faces (5,6), said transport faces (5,6) being in mutual abutment and configured such that the piece of laundry (2) is pulled of the conveyor (1) with its fold first and is subsequently conveyed onto the subjacent transport face (6).
Since the piece of laundry is hereby transferred with a fold and does not have to be oriented correctly, efficient introduction of pieces of laundry can be accomplished in a subsequent rotary ironed or the like, if any. Simultaneously as a result of the fact that the fold is established on one of the sides of the piece of laundry rather than at the top, at the conveyor, and that the fold is thereby capable of being introduced sideways between the two opposed transport faces, the machine can be constructed with a lower total height, ceteris Paribus.
Since the piece of laundry is conveyed away from the conveyor as soon as it arrives thereon the bar will quickly be ready for renewed feeding of a piece of laundry. This necessitates that the piece of laundry is introduced into the feeder with a longitudinal fold that is subsequently unfolded and that can optionally be straightened somewhere else in the machine.
According to a preferred embodiment the conveyor can comprise one or more plate elements (17) with an upper edge that extends along the entire length of the conveyor (11), longitudinally with that of the conveyor belt (16), and means for relative displacement of the upper edge of the conveyor elements to an upper and a lower position, wherein the upper edge extends upwards above and below, respectively, the upper face of the conveyor belt such that the piece of laundry.
According to a further preferred embodiment of the invention the opposed transport faces (5,6) each comprises a pair of rollers (7,8) that are located in close proximity to each other at the one side of the conveyor (11), and forms a space between the roller pairs (7,8) for introduction of the fold on the piece of laundry.
Besides, the means for forming a fold on one of the substantially freely suspended portions of the piece of laundry and the means for introducing the fold thus formed on the piece of laundry (2) between the two opposed transport faces (5,6) advantageously comprise a number of air nozzles that are located at the one side of the conveyor a distance below the uppermost face of the conveyor, said air nozzles being oriented towards the space between the two transport faces. Thereby a very simple and inexpensive introduction of pieces of laundry between the two transport faces is accomplished.
A convenient embodiment of the invention will be described in detail in the following with reference to the drawing, wherein:
FIG. 1 shows an apparatus according to the invention seen in a perspective view, and an operator;
FIG. 2a is a schematically sectional view of a detail of the apparatus according to FIG. 1;
FIG. 2b shows the detail according to FIG. 2a in another process posture;
FIG. 3 shows the apparatus according to FIG. 1 with a piece of laundry that has been transferred into the feeder with a fold; and
FIG. 4 shows the apparatus according to FIG. 3 wherein the piece of laundry is unfolded.